Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Income Tax Contingency [Line Items] | |||
| Change in valuation allowance (excluding impact of Tax Act) | $ 30,704 | $ 117,707 | $ 40,676 |
| Liability for unrecognized tax benefits | 5,395 | 4,628 | |
| Accrued interest and penalties related to uncertain tax positions | 2,100 | 1,900 | |
| Unrecognized tax benefits, interest on tax expense | 200 | ||
| Unrecognized tax benefits, tax penalties | 0 | ||
| Deferred tax valuation allowance | |||
| Income Tax Contingency [Line Items] | |||
| Charged to cost and expenses | $ (14,625) | $ 117,707 | $ 40,676 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of interest expense for an underpayment of income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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